Low oxide trench dishing chemical mechanical polishing

ABSTRACT

Chemical mechanical planarization (CMP) polishing compositions, methods and systems are provided to reduce oxide trench dishing and improve over-polishing window stability. High and tunable silicon oxide removal rates, low silicon nitride removal rates, and tunable SiO2: SiN selectivity are also provided. The compositions use unique chemical additives, such as maltitol, lactitol, maltotritol, ribitol, D-sorbitol, mannitol, dulcitol, iditol, D-(−)-Fructose, sorbitan, sucrose, ribose, Inositol, glucose, D-arabinose, L-arabinose, D-mannose, L-mannose, meso-erythritol, beta-lactose, arabinose, or combinations thereof as oxide trench dishing reducing additives.

CROSS REFERENCE TO RELATED PATENT APPLICATIONS

This application claims the benefit of priority under 35 U.S.C. § 119(e)to earlier filed U.S. patent application Ser. Nos. 62/692,633, and62/692,639 filed on Jun. 29, 2018, which are entirely incorporatedherein by reference.

BACKGROUND OF THE INVENTION

This invention relates to the chemical mechanical planarization (CMP) ofoxide and doped oxide films.

In the fabrication of microelectronics devices, an important stepinvolved is polishing, especially surfaces for chemical-mechanicalpolishing for the purpose of recovering a selected material and/orplanarizing the structure.

For example, a SiN layer is deposited under a SiO₂ layer to serve as apolish stop. The role of such polish stop is particularly important inShallow Trench Isolation (STI) structures. Selectivity ischaracteristically expressed as the ratio of the oxide polish rate tothe nitride polish rate. An example is an increased polishingselectivity rate of silicon dioxide (SiO₂) as compared to siliconnitride (SiN).

In the global planarization of patterned structures, reducing oxidetrench dishing is a key factor to be considered. The lower trench oxideloss will prevent electrical current leaking between adjacenttransistors. Non-uniform trench oxide loss across die (within Die) willaffect transistor performance and device fabrication yields. Severetrench oxide loss (high oxide trench dishing) will cause poor isolationof transistor resulting in device failure. Therefore, it is important toreduce trench oxide loss by reducing oxide trench dishing in CMPpolishing compositions.

U.S. Pat. No. 5,876,490 discloses the polishing compositions containingabrasive particles and exhibiting normal stress effects. The slurryfurther contains non-polishing particles resulting in reduced polishingrate at recesses, while the abrasive particles maintain high polishrates at elevations. This leads to improved planarization. Morespecifically, the slurry comprises cerium oxide particles and polymericelectrolyte, and can be used for Shallow Trench Isolation (STI)polishing applications.

U.S. Pat. No. 6,964,923 teaches the polishing compositions containingcerium oxide particles and polymeric electrolyte for Shallow TrenchIsolation (STI) polishing applications. Polymeric electrolyte being usedincludes the salts of polyacrylic acid, similar as those in U.S. Pat.No. 5,876,490. Ceria, alumina, silica & zirconia are used as abrasives.Molecular weight for such listed polyelectrolyte is from 300 to 20,000,but in overall, <100,000.

U.S. Pat. No. 6,616,514 discloses a chemical mechanical polishing slurryfor use in removing a first substance from a surface of an article inpreference to silicon nitride by chemical mechanical polishing. Thechemical mechanical polishing slurry according to the invention includesan abrasive, an aqueous medium, and an organic polyol that does notdissociate protons, said organic polyol including a compound having atleast three hydroxyl groups that are not dissociable in the aqueousmedium, or a polymer formed from at least one monomer having at leastthree hydroxyl groups that are not dissociable in the aqueous medium.

U.S. Pat. No. 6,544,892 teaches the polishing compositions containingusing abrasive, and an organic compound having a carboxylic acidfunctional group and a second functional group selected from amines andhalides. Ceria particles were used as abrasives.

However, those prior disclosed Shallow Trench Isolation (STI) polishingcompositions did not address the importance of oxide trench dishingreducing.

It should be readily apparent from the foregoing that there remains aneed within the art for compositions, methods and systems of chemicalmechanical polishing that can afford the reduced oxide trench dishingand improved over polishing window stability in a chemical andmechanical polishing (CMP) process, in addition to high removal rate ofsilicon dioxide as well as high selectivity for silicon dioxide tosilicon nitride.

BRIEF SUMMARY OF THE INVENTION

The present invention provides Chemical mechanical polishing (CMP)polishing compositions, methods and systems for a reduced oxide trenchdishing and thus improved over polishing window stability by introducingchemical additives as oxide trench dishing reducing additivescompositions at wide pH range including acidic, neutral and alkaline pHconditions.

The present invention also provides the benefits of achieving high oxidefilm removal rates, low SiN film removal rates, high and tunable Oxide:SiN selectivity, lower total defect counts post-polishing, and excellentmean particle size (nm) stability.

In one aspect, there is provided a CMP polishing composition comprises:

abrasive particles selected from the group consisting of inorganic oxideparticles, metal-coated inorganic oxide particles, organic polymerparticles, metal oxide-coated organic polymer particles and combinationsthereof;

chemical additive as oxide trenching dishing reducer,

a solvent; and

optionally

biocide; and

pH adjuster;

wherein the composition has a pH of 2 to 12, preferably 3 to 10, andmore preferably 4 to 9.

The inorganic oxide particles include but are not limited to ceria,colloidal silica, high purity colloidal silica, colloidal ceria,alumina, titania, zirconia particles.

An example of ceria particles are calcined ceria particles. An exampleof calcined ceria particles are calcined ceria particles manufacturedfrom milling process.

An example of colloidal ceria particles is typically manufactured fromchemical reactions and crystallization processes.

The metal-coated inorganic oxide particles include but are not limitedto the ceria-coated inorganic oxide particles, such as, ceria-coatedcolloidal silica, ceria-coated high purity colloidal silica,ceria-coated alumina, ceria-coated titania, ceria-coated zirconia, orany other ceria-coated inorganic oxide particles.

The organic polymer particles include, but are not limited to,polystyrene particles, polyurethane particle, polyacrylate particles, orany other organic polymer particles.

The metal-coated organic polymer particles are selected from the groupconsisting of ceria-coated organic polymer particles, zirconia-coatedorganic polymer particles, silica-coated organic polymer particles, andcombinations thereof.

The preferred abrasive particles are ceria-coated inorganic oxideparticles and ceria particle. More preferred abrasive particles areceria-coated silica particles and calcined ceria particles.

The solvent includes but is not limited to deionized (DI) water,distilled water, and alcoholic organic solvents.

The chemical additives as oxide trenching dishing reducers contain atleast two or more, preferably four or more, more preferably six or morehydroxyl functional groups in their molecular structures.

In one embodiment, the chemical additive has a general molecularstructure as shown below:

In the general molecular structure, n is selected from 2 to 5,000, from3 to 12, preferably from 4 to 7.

R1, R2, and R3 can be the same or different atoms or functional groups.

Each of Rs in the group of R1 to R3 can be independently selected fromthe group consisting of hydrogen, alkyl, alkoxy, organic group with oneor more hydroxyl groups, substituted organic sulfonic acid, substitutedorganic sulfonic acid salt, substituted organic carboxylic acid,substituted organic carboxylic acid salt, organic carboxylic ester,organic amine groups, and combinations thereof; wherein, at least two ormore, preferably four of them are hydrogen atoms.

When R1, R2, and R3 are the same and are hydrogen atoms, the chemicaladditive bears multi hydroxyl functional groups.

The molecular structures of some examples of such chemical additives arelisted below:

In another embodiment, the chemical additive has a structure shownbelow:

In this structure, one —CHO functional group is located at one end ofthe molecule as the terminal functional group; n is selected from 2 to5,000, from 3 to 12, preferably from 4 to 7.

Each of R1 and R2 can be independently selected from the groupconsisting of hydrogen, alkyl, alkoxy, organic group with one or morehydroxyl groups, substituted organic sulfonic acid, substituted organicsulfonic acid salt, substituted organic carboxylic acid, substitutedorganic carboxylic acid salt, organic carboxylic ester, organic aminegroups, and combinations thereof.

When R1 and R2 are all hydrogen atoms, and n=3, the chemical additive isD-arabinose or L-arabinose:

When R1 and R2 are all hydrogen atoms, and n=4, the chemical additive isD-mannose or L-mannose.

In yet another embodiment, the chemical additive has a molecularstructure selected from the group comprising of at least one (f), atleast one (g), at least one (h) and combinations thereof;

In these general molecular structures; R1, R2, R3, R4, R5, R6, R7 R8,R9, R10, R11, R12, R13, and R14 can be the same or different atoms orfunctional groups.

They can be independently selected from the group consisting ofhydrogen, alkyl, alkoxy, organic group with one or more hydroxyl groups,substituted organic sulfonic acid, substituted organic sulfonic acidsalt, substituted organic carboxylic acid, substituted organiccarboxylic acid salt, organic carboxylic ester, organic amine groups,and combinations thereof; wherein, at least two or more, preferably fouror more of them are hydrogen atoms.

When R1, R2, R3 R4, R5, R6, R7 R8, R9, R10, R11, R12, R13, and R14 areall hydrogen atoms which provide the chemical additives bearing multihydroxyl functional groups.

The molecular structures of some examples of such chemical additives arelisted below:

Yet, in another embodiment, the chemical additives contain at least onesix-member ring structure motif ether bonded with at least one polyolmolecular unit containing multiple hydroxyl functional groups in themolecular unit structures or at least one polyol molecular unitcontaining multiple hydroxyl functional groups in the molecular unitstructures and at least one six-member ring polyol. A polyol is anorganic compound containing hydroxyl groups.

The chemical additives as oxide trenching dishing reducers contain atleast two, at least four, or at least six hydroxyl functional groups intheir molecular structures.

The general molecular structure for the chemical additives is shown in(a):

In one embodiment, at least one R in the group of R1 to R5 in thegeneral molecular structure is a polyol molecular unit having astructure shown in (b):

wherein n and m can be the same or different. m or n is independentlyselected from 1 to 5, preferably from 1 to 4, more preferably from 1 to3, and most preferably from 1 to 2; R6 to R9 can be the same ordifferent atoms or functional groups; andthe rest of Rs in the group of R1 to R5 can be independently selectedfrom the group consisting of hydrogen, alkyl, alkoxy, organic group withone or more hydroxyl groups, substituted organic sulfonic acid or salt,substituted organic carboxylic acid or salt, organic carboxylic ester,organic amine, and combinations thereof.

In another embodiment, at least one R in the group of R1 to R5 in thegeneral molecular structure is a polyol molecular unit having astructure shown in (b); at least one R in the group of R1 to R5 in thegeneral molecular structure is a six-member ring polyol as shown in (c):

wherein

-   -   one of OR in group of OR11, OR12, OR13 and OR14 will be replaced        by O in structure (a); and    -   R10 and each of other R in group of R10, R11, R12, R13 and R14        is independently selected from the group consisting of hydrogen,        alkyl, alkoxy, organic group with one or more hydroxyl groups,        substituted organic sulfonic acid or salt, substituted organic        carboxylic acid or salt, organic carboxylic ester, organic        amine, and combinations thereof;        and the rest of Rs in the group of R1 to R5 can be independently        selected from the group consisting of hydrogen, alkyl, alkoxy,        organic group with one or more hydroxyl groups, substituted        organic sulfonic acid or salt, substituted organic carboxylic        acid or salt, organic carboxylic ester, organic amine, and        combinations thereof.

In the general molecular structure, at least two, preferably four, morepreferably six of the Rs in the group of R1 to R9 are hydrogen atoms.

When only one R, such as R5 in the group of R1 to R5 in the generalmolecular structure is a polyol molecular unit (b) having n=2 and m=1;and all rest of Rs in the group of R1 to R9 are all hydrogen atoms, thefollowing two chemical additives are obtained:

When one R, such as R5 is a polyol molecular unit (b) having n=2 andm=1; and one R, such as R2 is a six-member ring polyol; and all rest ofRs in the group of R1 to R14 are all hydrogen atoms, the followingchemical additive is obtained:

The chemical additive comprises maltitol, lactitol, maltotritol,ribitol, D-sorbitol, mannitol, dulcitol, iditol, D-(−)-Fructose,sorbitan, sucrose, ribose, Inositol, glucose, D-arabinose, L-arabinose,D-mannose, L-mannose, meso-erythritol, beta-lactose, arabinose, andcombinations thereof. The preferred chemical additives are maltitol,lactitol, maltotritol, D-sorbitol, mannitol, dulcitol, iditol,D-(−)-Fructose, sucrose, ribose, Inositol, glucose. D-mannose,L-mannose, beta-lactose, and combinations thereof. The more preferredchemical additives are maltitol, lactitol, maltotritol, D-sorbitol,mannitol, dulcitol, D-(−)-Fructose, beta-lactose, and combinationsthereof.

In some embodiments, the CMP polishing compositions can be made into twoor more parts and mixed at the point of use.

In another aspect, there is provided a method of chemical mechanicalpolishing (CMP) a substrate having at least one surface comprisingsilicon dioxide (such tetraethyl orthosilicate or TEOS) using thechemical mechanical polishing (CMP) composition described above.

In yet another aspect, there is provided a system of chemical mechanicalpolishing (CMP) a substrate having at least one surface comprisingsilicon dioxide using the chemical mechanical polishing (CMP)composition described above.

The polished oxide films can be Chemical vapor deposition (CVD), PlasmaEnhance CVD (PECVD), High Density Deposition CVD (HDP), spin on oxidefilms, flowable CVD oxide film, carbon doped oxide film, nitrogen dopedoxide film, or combinations thereof.

The substrate disclosed above can further comprises a silicon nitride(SiN) surface. The removal selectivity of SiO₂: SiN is greater than 10,preferably greater than 20, and more preferably greater than 30.

BRIEF DESCRIPTION OF SEVERAL VIEWS OF THE DRAWINGS

FIG. 1. Depicts the effects of Ceria-coated Silica/D-Sorbitol Ratio onFilm RR (Å/min.)

FIG. 2. Depicts the effects of Ceria-coated Silica/D-Sorbitol Ratio onOxide Trench Dishing

DETAILED DESCRIPTION OF THE INVENTION

This invention relates to the Chemical mechanical polishing (CMP)compositions, methods and systems for oxide and doped oxide filmspolishing.

In the global planarization of patterned structures, reducing oxidetrench dishing is a key factor to be considered. The lower trench oxideloss will prevent electrical current leaking between adjacenttransistors. Non-uniform trench oxide loss across die or/and within Diewill affect transistor performance and device fabrication yields. Severetrench oxide loss (high oxide trench dishing) will cause poor isolationof transistor resulting in device failure. Therefore, it is important toreduce trench oxide loss by reducing oxide trench dishing in CMPpolishing compositions.

The CMP compositions comprise the unique combination of abrasiveparticles and the suitable chemical additives, such as maltitol,lactitol, and maltotritol, or any other chemical molecules with similarmolecular structures and functional groups.

This invention provides a reduced oxide trench dishing and thus improvedover polishing window stability by introducing chemical additives asoxide trench dishing reducing additives in the Chemical mechanicalpolishing (CMP) compositions at wide pH range including acidic, neutraland alkaline pH conditions.

The Chemical Mechanical Polishing (CMP) compositions provide high oxidefilm removal rates, low SiN film removal rates and high SiO₂: SiNselectivity.

The Chemical Mechanical Polishing (CMP) compositions also providedsignificant total defect count reduction while comparing the CMPpolishing compositions using calcinated ceria particles as abrasives.

The Chemical Mechanical Polishing (CMP) composition also furtherprovides excellent mean particle size and size distribution stabilityfor the abrasive particles which is very important in maintaining robustCMP polishing performances with minimized polishing performancevariations.

In one aspect, there is provided a CMP polishing composition comprises:

abrasive particles selected from the group consisting of inorganic oxideparticles, metal-coated inorganic oxide particles, organic polymerparticles, metal oxide-coated organic polymer particles and combinationsthereof;

chemical additive as oxide trenching dishing reducer,

a solvent; and

optionally

biocide; and

pH adjuster;

wherein the composition has a pH of 2 to 12, preferably 3 to 10, andmore preferably 4 to 9.

The inorganic oxide particles include but are not limited to ceria,colloidal silica, high purity colloidal silica, colloidal ceria,alumina, titania, zirconia particles.

An example of ceria particles are calcined ceria particles. An exampleof calcined ceria particles are calcined ceria particles manufacturedfrom milling process.

An example of colloidal ceria particles is typically manufactured fromchemical reactions and crystallization processes.

The metal-coated inorganic oxide particles include but are not limitedto the ceria-coated inorganic oxide particles, such as, ceria-coatedcolloidal silica, ceria-coated high purity colloidal silica,ceria-coated alumina, ceria-coated titania, ceria-coated zirconia, orany other ceria-coated inorganic oxide particles.

The organic polymer particles include, but are not limited to,polystyrene particles, polyurethane particle, polyacrylate particles, orany other organic polymer particles.

The metal-coated organic polymer particles are selected from the groupconsisting of ceria-coated organic polymer particles, zirconia-coatedorganic polymer particles, silica-coated organic polymer particles, andcombinations thereof;

The average mean particle sizes or mean particle sizes (MPS) of theabrasive particles are ranged from 2 to 1,000 nm, 5 to 500 nm, 15 to 400nm or 25 to 250 nm. MPS refers to diameter of the particles and ismeasured using dynamic light scattering (DLS) technology.

The concentrations of these abrasive particles range from 0.01 wt. % to20 wt. %, the preferred concentrations range from 0.05 wt. % to 10 wt.%, the more preferred concentrations range from 0.1 wt. % to 5 wt. %.

The preferred abrasive particles are ceria-coated inorganic oxideparticles and ceria particle. More preferred abrasive particles areceria-coated silica particles and calcined ceria particles.

The solvent includes but is not limited to deionized (DI) water,distilled water, and alcoholic organic solvents.

The preferred solvent is DI water.

The CMP slurry may contain biocide from 0.0001 wt. % to 0.05 wt. %;preferably from 0.0005 wt. % to 0.025 wt. %, and more preferably from0.001 wt. % to 0.01 wt. %.

The biocide includes, but is not limited to, Kathon™, Kathon™ CG/ICP II,from Dupont/Dow Chemical Co. Bioban from Dupont/Dow Chemical Co. Theyhave active ingredients of 5-chloro-2-methyl-4-isothiazolin-3-one or2-methyl-4-isothiazolin-3-one.

The CMP slurry may contain a pH adjusting agent.

An acidic or basic pH adjusting agent can be used to adjust thepolishing compositions to the optimized pH value.

The pH adjusting agents include, but are not limited to nitric acid,hydrochloric acid, sulfuric acid, phosphoric acid, other inorganic ororganic acids, and mixtures thereof.

pH adjusting agents also include the basic pH adjusting agents, such assodium hydride, potassium hydroxide, ammonium hydroxide, tetraalkylammonium hydroxide, organic quaternary ammonium hydroxide compounds,organic amines, and other chemical reagents that can be used to adjustpH towards the more alkaline direction.

The CMP slurry contains 0 wt. % to 1 wt. %; preferably 0.01 wt. % to 0.5wt. %; more preferably 0.1 wt. % to 0.25 wt. % pH adjusting agent.

The CMP slurry contains 0.01 wt. % to 20 wt. %, 0.025 wt. % to 10 wt. %,0.05 wt. % to 5 wt. %, or 0.1 to 3.0 wt. % of the chemical additives asoxide trenching dishing and total defect count reducers.

The chemical additives as oxide trenching dishing reducers contain atleast two or more, preferably four or more, more preferably six or morehydroxyl functional groups in their molecular structures.

In one embodiment, the chemical additive has a general molecularstructure as shown below:

In the general molecular structure, n is selected from 2 to 5,000, from3 to 12, preferably from 4 to 7.

R1, R2, and R3 can be the same or different atoms or functional groups.

Each of Rs in the group of R1 to R3 can be independently selected fromthe group consisting of hydrogen, alkyl, alkoxy, organic group with oneor more hydroxyl groups, substituted organic sulfonic acid, substitutedorganic sulfonic acid salt, substituted organic carboxylic acid,substituted organic carboxylic acid salt, organic carboxylic ester,organic amine groups, and combinations thereof; wherein, at least two ormore, preferably four of them are hydrogen atoms.

When R1, R2, and R3 are the same and are hydrogen atoms, the chemicaladditive bears multi hydroxyl functional groups.

The molecular structures of some examples of such chemical additives arelisted below:

In another embodiment, the chemical additive has a structure shownbelow:

In this structure, one —CHO functional group is located at one end ofthe molecule as the terminal functional group; n is selected 2 to 5,000,from 3 to 12, preferably from 4 to 7.

R1 and R2 can be independently selected from the group consisting ofhydrogen, alkyl, alkoxy, organic group with one or more hydroxyl groups,substituted organic sulfonic acid, substituted organic sulfonic acidsalt, substituted organic carboxylic acid, substituted organiccarboxylic acid salt, organic carboxylic ester, organic amine groups,and combinations thereof.

When R1 and R2 are all hydrogen atoms, and n=3, the chemical additive isD-arabinose or L-arabinose.

When R1, R2 and R3 are all hydrogen atoms, and n=4, the chemicaladditive is D-mannose or L-mannose.

In yet another embodiment, the chemical additive has a molecularstructure selected from the group comprising of at least one (f), atleast one (g), at least one (h) and combinations thereof;

In these general molecular structures; R1, R2, R3, R4, R5, R6, R7 R8,R9, R10, R11, R12, R13, and R14 can be the same or different atoms orfunctional groups.

They can be independently selected from the group consisting ofhydrogen, alkyl, alkoxy, organic group with one or more hydroxyl groups,substituted organic sulfonic acid, substituted organic sulfonic acidsalt, substituted organic carboxylic acid, substituted organiccarboxylic acid salt, organic carboxylic ester, organic amine groups,and combinations thereof; wherein, at least two or more, preferably fouror more of them are hydrogen atoms.

When R1, R2, R3 R4, R5, R6, R7 R8, R9, R10, R11, R12, R13, and R14 areall hydrogen atoms which provide the chemical additives bearing multihydroxyl functional groups.

The molecular structures of some examples of such chemical additives arelisted below:

Yet, in another embodiment, the chemical additives contain at least onesix-member ring structure motif ether bonded with at least one polyolmolecular unit containing multiple hydroxyl functional groups in themolecular unit structures or at least one polyol molecular unitcontaining multiple hydroxyl functional groups in the molecular unitstructures and at least one six-member ring polyol. A polyol is anorganic compound containing hydroxyl groups.

The chemical additives as oxide trenching dishing reducers contain atleast two, at least four, or at least six hydroxyl functional groups intheir molecular structures.

The general molecular structure for the chemical additives is shown in(a):

In one embodiment, at least one R in the group of R1 to R5 in thegeneral molecular structure is a polyol molecular unit having astructure shown in (b):

wherein n and m can be the same or different. m or n is independentlyselected from 1 to 5, preferably from 1 to 4, more preferably from 1 to3, and most preferably from 1 to 2; R6 to R9 can be the same ordifferent atoms or functional groups; andthe rest of Rs in the group of R1 to R5 can be independently selectedfrom the group consisting of hydrogen, alkyl, alkoxy, organic group withone or more hydroxyl groups, substituted organic sulfonic acid or salt,substituted organic carboxylic acid or salt, organic carboxylic ester,organic amine, and combinations thereof.

In another embodiment, at least one R in the group of R1 to R5 in thegeneral molecular structure is a polyol molecular unit having astructure shown in (b); at least one R in the group of R1 to R5 in thegeneral molecular structure is a six-member ring polyol as shown in (c):

wherein

-   -   one of OR in group of OR11, OR12, OR13 and OR14 will be replaced        by O in structure (a); and    -   R10 and each of other R in group of R10, R11, R12, R13 and R14        is independently selected from the group consisting of hydrogen,        alkyl, alkoxy, organic group with one or more hydroxyl groups,        substituted organic sulfonic acid or salt, substituted organic        carboxylic acid or salt, organic carboxylic ester, organic        amine, and combinations thereof;        and the rest of Rs in the group of R1 to R5 can be independently        selected from the group consisting of hydrogen, alkyl, alkoxy,        organic group with one or more hydroxyl groups, substituted        organic sulfonic acid or salt, substituted organic carboxylic        acid or salt, organic carboxylic ester, organic amine, and        combinations thereof.

In the general molecular structure, at least two, preferably four, morepreferably six of the Rs in the group of R1 to R9 are hydrogen atoms.

When only one R, such as R5 in the group of R1 to R5 in the generalmolecular structure is a polyol molecular unit (b) having n=2 and m=1;and all rest of Rs in the group of R1 to R9 are all hydrogen atoms, thefollowing two chemical additives are obtained:

When one R, such as R5 is a polyol molecular unit (b) having n=2 andm=1; and one R, such as R2 is a six-member ring polyol; and all rest ofRs in the group of R1 to R14 are all hydrogen atoms, the followingchemical additive is obtained:

The chemical additive comprises maltitol, lactitol, maltotritol,ribitol, D-sorbitol, mannitol, dulcitol, iditol, D-(−)-Fructose,sorbitan, sucrose, Inositol, glucose, D-arabinose, L-arabinose,D-mannose, L-mannose, meso-erythritol, ribose, beta-lactose, andcombinations thereof. The preferred chemical additives are maltitol,lactitol, maltotritol, D-sorbitol, mannitol, dulcitol, iditol,D-(−)-Fructose, sucrose, ribose, Inositol, glucose. D-(+)-mannose,beta-lactose, and combinations thereof. The more preferred chemicaladditives are maltitol, lactitol, maltotritol, D-sorbitol, mannitol,dulcitol, D-(−)-Fructose, beta-lactose, and combinations thereof.

In some embodiments, the CMP polishing compositions can be made into twoor more parts and mixed at the point of use.

In another aspect, there is provided a method of chemical mechanicalpolishing (CMP) a substrate having at least one surface comprisingsilicon dioxide using the chemical mechanical polishing (CMP)composition described above. The polished oxide films can be CVD oxide,PECVD oxide, High density oxide, or Spin on oxide films.

The polished oxide films can be Chemical vapor deposition (CVD), PlasmaEnhance CVD (PECVD), High Density Deposition CVD (HDP), spin on oxidefilms, flowable CVD oxide film, carbon doped oxide film, nitrogen dopedoxide film, or combinations thereof.

The substrate disclosed above can further comprises a silicon nitridesurface. The removal selectivity of SiO₂: SiN is greater than 10,preferably greater than 20, and more preferably greater than 30.

Dishing performance of the CMP compositions can also be characterized bythe ratio of oxide trench dishing rate (Å/min.) vs the blanket HDP filmremoval rate (Å/min.).

The smaller of this ratio is, the lower oxide trench dishing is.

The CMP compositions having the ratio of ≤0.1, 0.08, 0.06, 0.05, 0.03,or 0.02 provide good oxide dishing performance.

In CMP polishing compositions, it is very important to keep abrasiveparticles stable to assure consistent desired CMP polishing performance.

When using the chemical additives in the CMP polishing compositions,these chemical additives can have some impacts on the stability ofabrasive particles in the compositions.

For example, when maltitol, lactitol or their derivatives, are used asoxide trench reducing agents in polishing compositions, these chemicaladditives can have some impacts on the stability of ceria-coatedinorganic oxide abrasives in the CMP polishing compositions.

Typically, the abrasive particle stability is tested by monitoring themean particle size (MPS) (nm) and particle size distribution parameterD99 (nm) changes vs the times or at elevated temperatures.

Particle size distribution may be quantified as a weight percentage ofparticles that has a size lower than a specified size. For example,parameter D99 (nm) represents a particle size (diameter) where 99 wt. %of all the slurry particles would have particle diameter equal to orsmaller than the D99 (nm). That is, D99 (nm) is a particle size that 99wt. % of the particles fall on and under.

The smaller of MPS (nm) and D99 (nm) changes, the more stable of theabrasive particles are and thus the CMP polishing compositions are.

Particle size distribution can be measured by any suitable techniquessuch as imaging, dynamic light scattering, hydrodynamic fluidfractionation, disc centrifuge etc.

MPS (nm) and D99 (nm) are both measured by dynamic light scattering inthis application.

CMP compositions providing abrasive particle stability have the changesfor MPS (nm) and D99 (nm)≤6.0%, 5.0%, 3.0%, 2.0%, 1.0%, 0.5%, 0.3% or0.1% for a shelf time of at least 30 days, 40 days, 50 days, 60 days, 70days or 100 days at a temperature ranging from 20 to 60° C., 25 to 50°C.

The following non-limiting examples are presented to further illustratethe present invention.

CMP Methodology

In the examples presented below, CMP experiments were run using theprocedures and experimental conditions given below.

Glossary Components

Calcinate ceria particles: used as abrasives having a particle size ofapproximately 150 nanometers (nm); such ceria-coated silica particlescan have a particle size of ranged from approximately 5 nanometers (nm)to 500 nanometers (nm).

Ceria-coated Silica: used as abrasive having a particle size ofapproximately 100 nanometers (nm); such ceria-coated silica particlescan have a particle size of ranged from approximately 5 nanometers (nm)to 500 nanometers (nm);

Ceria-coated Silica particles (with varied sizes) were supplied by JGCInc. in Japan.

Chemical additives, such as D-sorbitol, dulcitol, fructose, maltitol,lactitol and other chemical raw materials were supplied bySigma-Aldrich, St. Louis, Mo.

TEOS: tetraethyl orthosilicate

Polishing Pad: Polishing pad, IC1010 and other pads were used duringCMP, supplied by DOW, Inc.

Parameters General

Å or A: angstrom(s) —a unit of length

BP: back pressure, in psi units

CMP: chemical mechanical planarization=chemical mechanical polishing

CS: carrier speed

DF: Down force: pressure applied during CMP, units psi

min: minute(s)

ml: milliliter(s)

mV: millivolt(s)

psi: pounds per square inch

PS: platen rotational speed of polishing tool, in rpm (revolution(s) perminute)

SF: slurry flow, ml/min

Wt. %: weight percentage (of a listed component)

TEOS: SiN Selectivity: (removal rate of TEOS)/(removal rate of SiN)

HDP: high density plasma deposited TEOS

TEOS or HDP Removal Rates: Measured TEOS or HDP removal rate at a givendown pressure. The down pressure of the CMP tool was 2.5 psi, 3.0 psi or3.3 psi or 4.3 psi in the examples.

SiN Removal Rates: Measured SiN removal rate at a given down pressure.The down pressure of the CMP tool was 3.0 psi in the examples listed.

Metrology

Films were measured with a ResMap CDE, model 168, manufactured byCreative Design Engineering, Inc, 20565 Alves Dr., Cupertino, Calif.,95014. The ResMap tool is a four-point probe sheet resistance tool.Forty-nine-point diameter scan at 5 mm edge exclusion for film wastaken.

CMP Tool

The CMP tool that was used is a 200 mm Mirra, or 300 mm Reflexionmanufactured by Applied Materials, 3050 Boweres Avenue, Santa Clara,Calif., 95054. An IC1000 pad supplied by DOW, Inc, 451 Bellevue Rd.,Newark, Del. 19713 was used on platen 1 for blanket and pattern waferstudies.

The IC1010 pad or other pad was broken in by conditioning the pad for 18mins. At 7 lbs. down force on the conditioner. To qualify the toolsettings and the pad break-in two tungsten monitors and two TEOSmonitors were polished with Versum® STI2305 slurry, supplied by VersumMaterials Inc. at baseline conditions.

Wafers

Polishing experiments were conducted using PECVD or LECVD or HD TEOSwafers. These blanket wafers were purchased from Silicon ValleyMicroelectronics, 2985 Kifer Rd., Santa Clara, Calif. 95051.

Polishing Experiments

In blanket wafer studies, oxide blanket wafers, and SiN blanket waferswere polished at baseline conditions. The tool baseline conditions were:table speed; 87 rpm, head speed: 93 rpm, membrane pressure; 2.5 psi, 3.0psi or 3.3 psi or 4.3 psi, inter-tube pressure; 3.1 psi or others,retaining ring pressure; 5.1 psi or others,

The slurry was used in polishing experiments on patterned wafers(MIT860), supplied by SWK Associates, Inc. 2920 Scott Blvd. Santa Clara,Calif. 95054). These wafers were measured on the Veeco VX300profiler/AFM instrument. The 3 different sized pitch structures wereused for oxide dishing measurement. The wafer was measured at center,middle, and edge die positions.

TEOS: SiN Selectivity: (removal rate of TEOS)/(removal rate of SiN)obtained from the CMP polishing compositions were tunable.

WORKING EXAMPLES

In the following working examples, a polishing composition comprising0.2 wt. % cerium-coated silica, a biocide ranging from 0.0001 wt. % to0.05 wt. %, and deionized water was prepared as reference (ref.).

The polishing compositions were prepared with the reference (0.2 wt. %cerium-coated silica, a biocide ranging from 0.0001 wt. % to 0.05 wt. %,and deionized water) plus a chemical additive in 0.01 wt. % to 2.0 wt.%.

All examples, except pH condition examples the composition had a pH at5.35.

pH adjusting agent used for acidic pH condition and alkaline pHcondition were nitric acid and ammonium hydroxide respectively.

Example 1

The working slurries has 0.15 wt. % chemical additives added to thereference slurry.

The effects of various selected chemical additives on the film removalrates and selectivity were observed.

The removal rates (RR at Å/min) for different films were tested. Thetest results were listed in Table 1.

TABLE 1 Effects of Chemical Additives on Film RR (A/min.) & TEOS: SiNSelectivity TEOS-RR HDP-RR SiN-RR TEOS: SiN Samples (ang/min) (ang/min)(ang/min) Selectivity 0.2 wt. % Ceria-coated 3279 2718 349 9 Silica(Ref.) Ref. + 0.15 wt. % 2394 2299 75 32 D-Sorbitol Ref. + 0.15 wt. %2741 2372 124 22 D-Mannitol Ref. + 0.15 wt. % 2839 2104 148 19D-(+)-Mannose Ref. + 0.15 wt. % 2694 2256 109 25 Xylitol Ref. + 0.15 wt.% 2808 2064 366 8 meso-Erythritol

As the results showed in Table 1, the slurries based on ceria-coatedsilica offered higher removal rate for TEOS.

As the results further showed in Table 1, the chemical additivesD-sorbitol, D-mannitol, D-mannose, and xylitol, except meso-erythritolsuppressed SiN removal rates comparing with the Ref., while stillafforded high TEOS and HDP film removal rates and provided high Oxide:SiN selectivity.

Example 2

In Example 2, 0.2 wt. % ceria-coated silica abrasive based formulationwithout chemical additives was used as reference.

The chemical additives were used at 0.15 wt. % (0.15×) concentrationsrespectively with 0.2 wt. % ceria-coated silica as abrasives in theworking slurries.

The effects of various selected chemical additives on the oxidetrenching dishing vs over polishing times were observed.

The test results were listed in Table 2. HDP RR (Å/min.) from Table 1was also listed in Table 2.

TABLE 2 Effects of Chemical Additives on Oxide Trench Dishing & HDP RR(A/min.) Blanket HDP RR Compositions OP Time (sec.) 100 um pitch dishing200 um pitch dishing (A/min.) 0.2% Ceria-coated Silica pH 5.35 0 165 2912718 60 857 1096 120 1207 1531 0.2% Ceria-coated Silica + 0.15XD-Sorbitol 0 137 276 2299 60 247 411 120 380 544 0.2% Ceria-coatedSilica + 0.15X D-mannitol 0 162 285 2372 60 368 580 120 563 816 0.2%Ceria-coated Silica + 0.15X D-(+)- 0 181 272 2401 Mannose 60 660 973 1201121 1553 0.2% Ceria-coated Silica + 0.15X Xylitol 0 144 258 2256 60 485800 120 760 1166 0.2% Ceria-coated Silica + 0.15X meso- 0 131 265 2064Erythritol 60 732 896 120 1125 1392

TABLE 3 The Ratio of Trench Dishing Rate (Å)/Blanket HDP RR (Å/min.)P100 P200 Dishing Rate Dishing Rate (Å/min.)/Blanket (Å/min.)/BlanketCompositions HDP RR (Å/min.) HDP RR (Å/min.) 0.2% Ceria-coated Silica pH5.35 0.13 0.16 0.2% Ceria-coated Silica + 0.15X 0.06 0.06 D-Sorbitol0.2% Ceria-coated Silica + 0.15X 0.08 0.12 D-mannitol 0.2% Ceria-coatedSilica + 0.15X 0.2 0.24 D-(+)-Mannose 0.2% Ceria-coated Silica + 0.15X0.12 0.16 Xylitol 0.2% Ceria-coated Silica + 0.15X 0.19 0.24meso-Erythritol

Table 3 listed the ratio of oxide trench dishing rate (Å/min.) vs theblanket HDP film removal rate (Å/min.),

As the results shown in Tables 2 and 3, the addition of various chemicaladditives as oxide trench dishing reducer in polishing compositionsshowed different effects.

The polishing compositions using D-sorbitol and D-mannitol providedsignificant oxide trench dishing reductions on both 100 μm pitch and 200μm pitch respectively, comparing to the reference.

The polishing composition using xylitol showed no impact on oxide trenchdishing in polishing comparing to the reference. The polishingcompositions using D-(+)-mannose or meso-erythritol had the oxide trenchdishing worse than the reference.

The effects of chemical additives on the slopes of oxide trenchingdishing vs over polishing removal amounts were listed in Table 4.

TABLE 4 Effects of Chemical Additives on Slopes of Dishing vs OP RemovalAmount P100 P200 P1000 dishing/OP dishing/OP dishing/OP Compositions AmtSlope Amt Slope Amt Slope 0.2X Ceria-coated Silica 0.19 0.23 0.25 0.2XCeria-coated Silica + 0.05 0.06 0.08 0.15x D-Sorbitol 0.2X Ceria-coatedSilica + 0.08 0.11 0.40 0.15x D-Mannitol 0.2X Ceria Coated + 0.15x D-0.20 0.27 0.38 (+)-Mannose 0.2X Ceria-coated Silica + 0.14 0.20 0.410.15x Xylitol

As the results shown in Table 4, the polishing composition usingD-sorbitol or D-mannitol afforded much lower slope values of oxidetrench dishing vs over polishing amounts on 100 μm and 200 μm featureswhile comparing to the reference.

The other additives offered no dishing improvements comparing to thereference.

Example 3

The effects of various selected chemical additives on the film removalrates (RR at Å/min) and selectivity were observed. These chemicaladditives were used at 0.1 wt. % concentrations respectively with 0.2wt. % ceria-coated silica as abrasives.

The test results were listed in Table 5.

TABLE 5 Effects of Chemical Additives on Film RR (A/min.) & TEOS: SiNSelectivity TEOS-RR HDP-RR SiN-RR TEOS: SiN Samples (ang/min) (ang/min)(ang/min) Selectivity 0.2% Ceria-Coated 3279 2718 349 9.4 Silica +0.1xD-Sorbitol 2968 2814 92 32.3 +0.1x D-(−)-Fructose 1662 1781 34 48.9+0.1x Maltitol 2834 2679 38 74.6 +0.1x Dulcitol 3127 2995 45 69.5

As the results showed in Table 5, these chemical additives D-sorbitol,D-(−)-Fructose, Maltitol and Dulcitol suppressed SiN removal rates whilecomparing with reference, and still afforded high TEOS and HDP filmremoval rates.

TABLE 6 Effects of Chemical Additives on Oxide Trench Dishing & HDP RR(A/min.) OP 100 um 200 um 1000 um Blanket Time pitch pitch pitch HDP RRSamples (Sec.) dishing dishing dishing (A/min.) 0.2% Ceria-coated 0 165291 1013 2718 Silica 60 857 1096 1821 120 1207 1531 2392 0.2%Ceria-coated 0 98 184 432 2814 Silica + 0.1x 60 261 383 1494 D-Sorbitol120 418 583 1936 0.2% Ceria-coated 0 123 229 694 1781 Silica + 0.1x 60315 372 962 D-(−)-Fructose 120 458 527 1175 0.2% Ceria-coated 108 218620 620 2679 Silica + 0.1x 228 355 873 873 Maltitol 333 482 1068 10680.2% Ceria-coated 0 152 252 770 2995 Silica + 0.1x 60 238 370 10Dulcitol 120 366 495 1081

CMP composition having D-(−)-fructose suppressed removal of TEOS inaddition of SiN, but still afforded high TEOS: SiN selectivity.

The effects of various selected chemical additives on the oxidetrenching dishing vs over polishing times were observed.

The test results were listed in Table 6. HDP RR (A/min.) from Table 5was also listed in Table 6.

As the oxide trench dishing vs over polishing time results showed inTable 6, the CMP compositions with chemical additives afforded loweroxide trench dishing on 100 μm pitch, and 200 μm pitch, respectively.The compositions provided significant oxide trench dishing reductionscomparing to the reference composition.

Table 7 listed the ratio of oxide trench dishing rate (Å/min.) vs theblanket HDP film removal rate (Å/min.),

TABLE 7 The Ratio of Trench Dishing Rate (Å)/Blanket HDP RR (Å/min.)P100 Dishing Rate P200 Dishing Rate (Å/min.)/Blanket HDP(Å/min.)/Blanket HDP Compositions RR (Å/min.) RR (Å/min.) 0.2XCeria-coated Silica 0.13 0.16 +0.1x D-Sorbitol 0.06 0.07 +0.1xD-(−)-Fructose 0.08 0.09 +0.1x Maltitol 0.05 0.07 +0.1x Dulcitol 0.040.04

As the results shown in Table 7, the addition of the chemical additivesto the polishing compositions significantly reduced the ratio of trenchdishing rate vs the blanket HDP film removal rates than the ratioobtained from the reference sample at pH 5.35.

The slopes of the various sized pitch dishing vs oxide over polishingamounts were listed in Table 8.

As the results of slopes of the various sized pitch dishing vs oxideover polishing amounts showed in Table 8, the chemical additives andceria-coated silica abrasives based CMP polishing compositions affordedmuch lower slope values comparing to those slope values obtained fromthe reference.

TABLE 8 Effects of Chemical Additives on Slopes of Dishing vs OP RemovalAmount P100 P200 P1000 dishing/OP dishing/OP dishing/OP Compositions AmtSlope Amt Slope Amt Slope 0.2X Ceria-coated Silica 0.19 0.23 0.25 +0.1xD-Sorbitol 0.06 0.07 0.27 +0.1x D-(−)-Fructose 0.09 0.08 0.14 +0.1xMaltitol 0.04 0.05 0.08 +0.1x Dulcitol 0.04 0.04 0.05

Example 4

In Example 4, the removal rates, and TEOS: SiN selectivity were testedtests were performed with CMP polishing compositions with chemicaladditives having different concentrations at pH 5.35.

The test results were listed in Table 9.

TABLE 9 Effects of Additive Conc. on Film RR (A/min.) & Selectivity ofOxide: SiN TEOS-RR HDP-RR SiN-RR TEOS: Samples (ang/min) (ang/min)(ang/min) SiN Sel. 0.2% Ceria-coated Silica + 3595 3128 110 33 0.05xD-Sorbitol 0.2% Ceria-coated Silica + 3821 3425 112 34 0.1x D-Sorbitol0.2% Ceria-coated Silica + 3651 3517 83 44 0.15x D-Sorbitol

As the results showed in Table 9, when the concentration of D-sorbitolused in the compositions increased, similar TEOS removal rates wereobtained, and HPD film removal rates were increased and TEOS: SiNselectivity were also increased slightly or significantly.

The effects on the oxide trenching dishing vs over polishing times fromthe selected chemical additive D-sorbitol concentrations on the varioussized pitch features were tested.

The test results were listed in Table 10.

TABLE 10 Effects of Chemical Additive D-Sorbitol Conc. On Oxide TrenchDishing vs OP Times (sec.) 100 um 200 um Polish Time pitch pitch BlanketCompositions (Sec.) dishing dishing HDP RR 0.2% Ceria-coated 0 198 3323128 Silica + 0.05x D- 60 453 690 Sorbitol 120 573 842 0.2% Ceria-coated0 182 288 3425 Silica + 0.1x D-Sorbitol 60 355 551 120 499 736 0.2%Ceria-coated 0 132 246 3517 Silica + 0.15x D- 60 269 423 Sorbitol 120423 595

As the results showed in Table 10, all 3 tested CMP polishingcompositions contained D-sorbitol with different concentrations gave lowoxide trench dishing on both 100 μm pitch and 200 μm pitch.

Also, as the chemical additive D-sorbitol concentrations increased, theoxide trench dishing are further reduced.

As the results showed in Table 10, all 3 tested CMP polishingcompositions contained D-sorbitol with different concentrations gave lowoxide trench dishing on both 100 μm pitch and 200 μm pitch.

Also, as the chemical additive D-sorbitol concentrations increased, theoxide trench dishing are further reduced.

TABLE 11 Ratio of Trench Dishing Rate (Å)/Blanket HDP RR (Å/min.) vsConc. of D-Sorbitol P100 Dishing Rate P200 Dishing Rate (Å/min.)/BlanketHDP (Å/min.)/Blanket HDP Compositions RR (Å/min.) RR (Å/min.) 0.2%Ceria-coated 0.04 0.05 Silica + 0.05X D-Sorbitol 0.2% Ceria-coated 0.040.05 Silica + 0.1X D-Sorbitol 0.2% Ceria-coated 0.04 0.05 Silica + 0.15XD-Sorbitol

Table 11 listed the ratio of Trench Dishing Rate (A)/Blanket HDP RR(Å/min.) from the compositions with different concentrations ofD-Sorbitol.

As the results shown in Table 11, D-sorbitol used in the composition atpH 5.35, all significantly reduced the ratio of trench dishing rate vsthe blanket HDP film removal rates across the different testedconcentrations.

Therefore, D-sorbitol can be used as an effective oxide trench dishingreducer in the wide concentration range

The slopes of the various sized pitch dishing vs oxide over polishingamounts were tested and the results were listed in Table 12.

TABLE 12 Effects of Additive Conc. on Slopes of Dishing vs OP RemovalAmount P100 dishing/OP P200 dishing/OP Compositions Amt Slope Amt SlopeSTI2305 (Reference) 0.01 0.01 0.2% Ceria-coated Silica + 0.06 0.08 0.05xD-Sorbitol 0.2% Ceria-coated Silica + 0.05 0.07 0.1x D-Sorbitol 0.2%Ceria-coated Silica + 0.04 0.05 0.15x D-Sorbitol

As the results of slopes of the various sized pitch dishing vs oxideover polishing amounts showed in Table 12, different concentrations ofD-sorbitol in CMP polishing compositions all afforded similar slopevalues comparing to the reference sample.

Also, as the D-sorbitol concentration increased, the slopes of thevarious sized pitch dishing vs oxide over polishing while at overpolishing time at zero seconds gradually decreased.

Example 5

In Example 5, the tests were performed with CMP polishing compositionshaving different pH values.

The composition composed of 0.2 wt. % ceria-coated silica as abrasivesand 0.1 wt. % D-sorbitol as chemical additive was tested at threedifferent pH conditions.

The removal rates (RR at Å/min) for different films were tested. Thetest results were listed in Table 13.

TABLE 13 Effects of pH on Film RR (A/min.) & Selectivity of Oxide: SiN0.2% Ceria-coated Silica + 0.1% D- TEOS-RR HDP-RR SiN-RR TEOS: Sorbitol(ang/min) (ang/min) (ang/min) SiN Sel. pH 5.35 3821 3425 112 34 pH 63759 3415 131 29 pH 8 2932 3084 94 31

As the results showed in Table 10, the compositions showed a consistentperformance by offering high TEOS and HDP film removal rates, low SiNremoval rates, and high TEOS: SiN selectivity in acidic, neutral oralkaline pH conditions.

The test results on the effects of pH conditions using the CMP polishcompositions on oxide trench dishing vs over polishing times were listedin Table 14.

As the results showed in Table 14, similar oxide trenching dishing vsover polishing times and HDP film removal rates were obtained for thesame concentration of ceria-coated silica as abrasives and D-sorbitol asoxide trenching dishing reducing agent at 3 different pH conditions.

TABLE 14 Effects of pH Conditions on Oxide Trench Dishing vs OverPolishing Times (sec.) & HDP Film RR (A/min.) Polish 100 um Time pitch200 um pitch Blanket Compositions & pH (Sec.) dishing dishing HDP RR0.2% Ceria-coated Silica + 0 182 288 3425 0.1x D-Sorbitol (pH 60 355 5515.35) 120 499 736 0.2% Ceria-coated Silica + 0 169 325 3415 0.1xD-Sorbitol (pH 6) 60 354 566 120 506 800 0.2% Ceria-coated Silica + 0193 360 3084 0.1x D-Sorbitol (pH 8) 60 391 615 120 537 814

Table 15 showed the results of the ratio of Trench Dishing Rate(Å)/Blanket HDP RR (Å/min.),

TABLE 15 Ratio of Trench Dishing Rate (Å)/Blanket HDP RR (Å/min.) atDifferent pH P100 Dishing Rate P200 Dishing Rate (Å/min.)/Blanket(Å/min.)/Blanket Compositions HDP RR (Å/min.) HDP RR (Å/min.) 0.2%Ceria-coated Silica + 0.04 0.05 0.1X D-Sorbitol (pH 5.35) 0.2%Ceria-coated Silica + 0.04 0.07 0.1X D-Sorbitol (pH 6) 0.2% Ceria-coatedSilica + 0.05 0.06 0.1X D-Sorbitol (pH 7)

As the results shown in Table 15, the addition of the chemicaladditives, D-sorbitol, used as oxide trench dishing reducer in polishingcompositions at different pH conditions, showed significantly reductionof the ratio which indicated that D-sorbitol can be used as a veryeffective oxide trench dishing reducing agent at wide pH window.

Example 6

In Example 6, the effects of various selected chemical additives fromafore listed several types of chemical additives on the film removalrates and selectivity were observed.

The same molar concentrations of all tested chemical additives at 8.132mM was used respectively.

All examples, except examples for the pH condition test had a pH at5.35.

For the examples used in the pH condition test, pH adjusting agent wasused for acidic pH condition and alkaline pH condition were nitric acidand ammonium hydroxide respectively.

The removal rates (RR at Å/min) and removal selectivity for differentfilms were tested. The test results were listed in Table 16.

TABLE 16 Effects of 8.132 mM Concentration of Chemical Additives on FilmRR (A/min.) & TEOS: SiN Selectivity TEOS RR HDP RR PECVD SiN TEOS: SiNCompositions (A/min) (A/min) RR (A/min) Selectivity 0.2% Ceria-coated2754 1886 432 6.4 Silica 0.2% Ceria-coated 2609 2493 45 58.4 Silica +8.132 mM Maltitol 0.2% Ceria-coated 2862 2512 114 25.1 Silica + 8.132 mMRibose 0.2% Ceria-coated 2963 1985 393 7.5 Silica + 8.132 mM Arabinose0.2% Ceria-coated 2913 2186 115 25.3 Silica + 8.132 mM Beta-lactose 0.2%Ceria-coated 2899 2028 201 14.4 Silica + 8.132 mM Myo-inositol

As the results showed in Table 16, these chemical additives, when usedat 8.132 mM concentrations in the polishing compositions affordedsimilar TEOS film removal rates, HDP film removal rates, slightly orsignificantly suppressed SiN removal rates comparing with the reference.

The Oxide: SiN selectivity was fluctuating from slightly increased(arabinose, myo-inositol) to significantly increased (maltitol, riboseand beta-lactose). Among these tested chemical, maltitol showed as themost efficient SiN removal rate suppressing chemical additive, andribose and beta-lactose also showed as quite efficient SiN removal ratesuppressing additives.

Example 7

The following chemical additives, maltitol, D-sorbitol, lactitol,ribose, and beta-lactose were used in the polishing compositions with0.2 wt. % ceria-coated silica abrasives at pH 5.35 to have conductedpolishing tests on polishing oxide patterned wafers. The chemicaladditives were used at 0.15 wt. % in the compositions.

The effects of various chemical additives on the film removal rates andselectivity were observed.

The test results were listed in Table 17.

TABLE 17 Effects of Chemical Additives on Film RR (A/min.) & TEOS: SiNSelectivity TEOS HDP RR RR SiN RR TEOS: SiN Composition (A/min) (A/min)(A/min) Selectivity 0.2% Ceria-coated 4310 3047 557 8 Silica pH 5.350.2% Ceria-coated 3605 3992 65 36 Silica + 0.15% D-sorbitol 0.2% CPOP +0.15% Maltitol 4505 4203 61 39 0.2% CPOP + 0.15% Lactitol 4563 4183 8541 0.2% CPOP + 0.15% Ribose 4517 4325 103 39 0.2% CPOP + 0.15% 4716 404980 46 Beta-Lactose

As the results showed in Table 17, all compositions afforded similarhigh TEOS film removal rates, increased HDP film high removal rates,significantly suppressed SiN removal rates, significantly increasedOxide: SiN selectivity comparing with the reference sample.

The effects of various chemical additives on the oxide trenching dishingvs over polishing times were observed. These chemical additives wereused at 0.15 wt. % (0.15×) concentrations respectively with 0.2 wt. %ceria-coated silica as abrasive, and with all formulations at pH 5.35.

The test results were listed in Table 18.

As the oxide trench dishing vs over polishing time results showed inTable 18, all of these chemical additives, when used with ceria-coatedsilica abrasives in the CMP polishing compositions, afforded largelyreduced oxide trench dishing vs over polishing times at 60 seconds or120 seconds respectively on 100 μm pitch and 200 μm pitch features, andprovided significant oxide trench dishing reductions comparing to thereference.

TABLE 18 Effects of Chemical Additives on Oxide Trench Dishing & HDP RR(A/min.) OP Time 100 um pitch 200 um pitch Compositions (sec.) dishingdishing 0.2% Ceria-coated Silica 0 165 291 pH 5.35 60 857 1096 120 12071531 0.2% Ceria-coated 0 94 222 Silica + 0.15% Sorbitol 60 216 351 120314 475 0.2% Ceria-coated Silica + 0 135 261 0.15% Maltitol 60 293 463120 413 641 0.2% Ceria-coated Silica + 0 120 193 0.15% Lactitol 60 313436 120 468 646 0.2% Ceria-coated Silica + 0 88 176 0.15% Ribose 60 290409 120 441 606 0.2% Ceria-coated Silica + 0 141 259 0.15% Beta-Lactose60 387 587 120 579 870

As the oxide trench dishing vs over polishing time results showed inTable 18, all of these chemical additives, when used with ceria-coatedsilica abrasives in the CMP polishing compositions, afforded largelyreduced oxide trench dishing vs over polishing times at 60 seconds or120 seconds respectively on 100 μm pitch and 200 μm pitch features, andprovided significant oxide trench dishing reductions comparing to thereference.

Table 19 showed the results of the ratio of Trench Dishing Rate(Å)/Blanket HDP RR (Å/min.),

TABLE 19 Ratio of Trench Dishing Rate (Å)/Blanket HDP RR (Å/min.) P100Dishing Rate P200 Dishing Rate (Å/min.)/Blanket HDP (Å/min.)/BlanketCompositions RR (Å/min.) HDP RR (Å/min.) 0.2% Ceria-coated 0.13 0.16Silica pH 5.35 0.2% Ceria-coated 0.02 0.03 Silica + 0.15% Sorbitol 0.2%Ceria-coated 0.05 0.04 Silica + 0.15% Maltitol 0.2% Ceria-coated 0.040.05 Silica + 0.15% Lactitol 0.2% Ceria-coated 0.03 0.05 Silica + 0.15%Ribose 0.2% Ceria-coated Silica + 0.05 0.07 0.15% Beta-Lactose

As the results shown in Table 19, all tested polishing compositionsusing chemical additives showed significantly reduction of the ratio oftrench dishing rate vs the blanket HDP film removal rates whichindicated that all these chemical additives can be used as veryeffective oxide trench dishing reducing agents in the invented CMPpolishing compositions.

Working Example 8

The polishing compositions were prepared with the reference (0.2 wt. %ceria-coated silica, a biocide ranging from 0.0001 wt. % to 0.05 wt. %,and deionized water) and maltitol or lactitol were used at 0.28 wt. %.

All example compositions had a pH at 5.35.

The removal rates (RR at Å/min) for different films were tested. Theeffects of two selected chemical additives, maltitol and lactitol on thefilm removal rates and selectivity were observed.

The test results were listed in Table 20.

TABLE 20 Effects of Maltitol or Lactitol on Film RR (Å/min.) & TEOS: SiNSelectivity TEOS Film HDP SiN TEOS: RR (Å/ Film RR Film RR SiNCompositions min.) (Å/min.) (Å/min.) Selectivity 0.2% Ceria-coatedSilica 3279 2718 349 9.4 pH 5.35 0.2% Ceria-coated Silica + 2623 2639 4657.0 0.28% Maltitol pH 5.35 0.2% Ceria-coated Silica + 2630 2547 55 47.80.28% Lactitol pH 5.35

As the results shown in Table 20, the addition of the chemicaladditives, maltitol or lactitol, in the polishing compositions,significantly suppressed SiN removal rates while still afforded highTEOS and HDP film removal rates, thus, significantly increased Oxide:SiN film polishing selectivity.

Example 9

The example compositions in Example 8 were used in this Example.

Oxide trenching dishing for without/or with different over polishingtimes were tested. The effects of maltitol or lactitol on the oxidetrenching dishing vs over polishing times were observed.

The test results were listed in Table 21.

TABLE 21 Effects of Maltitol or Lactitol on Oxide Trench Dishing vs OPTimes (Sec.) OP Times 100 um pitch 200 um pitch Compositions (Sec.)dishing dishing 0.2% Ceria-coated Silica 0 165 291 pH 5.35 Ref. 60 8571096 120 1207 1531 0.2% Ceria-coated Silica + 0 408 616 0.28% MaltitolpH 5.35 60 480 713 120 542 803 0.2% Ceria-coated Silica + 0 349 5630.28% Lactitol pH 5.35 60 438 702 120 510 779

As the results shown in Table 21, the polishing compositions with theaddition of the chemical additives, maltitol or lactitol, afforded lowoxide trench dishing on 100 μm pitch, and 200 μm pitch respectively when60 second or 120 second over polishing times were applied.

The compositions provided significant oxide trench dishing reductionscomparing to the reference composition which did not have the chemicaladditives, maltitol or lactitol.

Table 22 showed the results of the ratio of Trench Dishing Rate(Å)/Blanket HDP RR (Å/min.),

TABLE 22 The Ratio of Trench Dishing Rate (A)/Blanket HDP RR (A/min.)P100 Dishing P200 Dishing Rate (Å/min.)/ Rate (Å/min.) / Blanket HDPBlanket HDP Compositions RR (A/min.) RR (A/min.) 0.2% Ceria-coatedSilica pH 5.35 0.13 0.16 0.2% Ceria-coated Silica + 0.28% 0.02 0.03Maltitol pH 5.35 0.2% Ceria-coated Silica + 0.28% 0.03 0.03 Lactitol pH5.35

As the results shown in Table 22, the addition of either maltitol orlactitol as oxide trench dishing reducer in polishing compositionssignificantly reduced the ratio of trench dishing rate vs the blanketHDP film removal rates, the lower of this ratio is, the lower of oxidetrench dishing is.

The slopes of oxide trench dishing vs the OP removal amount was showedin Table 23.

TABLE 23 Effects of Maltitol or Lactitol on Slopes of Dishing vs OPRemoval Amount P100 P200 P1000 dishing/OP dishing/OP dishing/OPCompositions Amt Slope Amt Slope Amt Slope 0.2% Ceria-coated Silica 0.190.23 0.25 pH 5.35 Ref. 0.2% Ceria-coated Silica + 0.04 0.05 0.08 0.28%Maltitol pH 5.35 0.2% Ceria-coated Silica + 0.04 0.06 0.09 0.28%Lactitol pH 5.35

The results listed in Table 23 indicated that the compositions withchemical additives, maltitol or lactitol provided lower slopes whichindicated good over polishing window for maintaining low oxide trenchdishing even more oxide film removed in over polishing steps.

As showing in Table 23, these chemical additives, maltitol or lactitol,and ceria-coated silica based CMP polishing compositions again showedmuch lower slope values comparing to those slope values obtained for theceria-coated silica abrasive based reference sample.

Example 10

In Example 10, the trench oxide loss rates were compared for thepolishing compositions using maltitol or lactitol and reference aslisted in Table 24.

TABLE 24 Effects of Maltitol or Lactitol on Trench Loss Rates (Å/min.)P100Trench P200Trench Loss Rate Loss Rate Compositions (Å/sec.) (Å/sec.)0.2% Ceria-coated Silica pH 5.35 18.5 19.3 Ref. 0.2% Ceria-coatedSilica + 2.0 2.5 0.28% Maltitol pH 5.35 0.2% Ceria-coated Silica + 2.32.6 0.28% Lactitol pH 5.35

As the results shown in Table 24, the addition of maltitol or lactitolas oxide trench dishing reducing agent into the polishing compositions,the trench loss rates were significantly reduced vs the reference samplewithout using any chemical additives.

Example 11

The compositions were prepared as shown in Table 19.

The compositions used of 0.2 wt. % ceria-coated silica as abrasives,0.28 wt. % lactitol as chemical additive, biocide, DI water, and a pHadjusting agent to provide different pH conditions.

The removal rates (RR at Å/min) for different films were tested. Theeffects of pH conditions on the film removal rates and selectivity wereobserved.

The test results were listed in Table 25.

TABLE 25 Effects of pH on Film RR (Å/min) & Selectivity of Oxide: SiNTEOS Film HDP SiN TEOS: RR (Å/ Film RR Film RR SiN Compositions min.)(Å/min.) (Å/min.) Selectivity 0.2% Ceria-coated Silica 3279 2718 349 9.4pH 5.35 0.2% Ceria-coated Silica + 2623 2639 46 57.0 0.28% Lactitol pH5.35 0.2% Ceria-coated Silica + 2524 2517 56 45.1 0.28% Lactitol pH 7.00.2% Ceria-coated Silica + 2401 2417 52 46.2 0.28% Lactitol pH 8.0

As the results shown in Table 25, the addition of lactitol as oxidetrench dishing reducing agent into the polishing compositions at threedifferent pH conditions, (acidic, neutral or alkaline) gave similar TEOSand HDP film removal rates, very effectively suppressed SiN film removalrates, and yielded much higher TEOS: SiN selectivity than the referencesample without using lactitol as chemical additive.

Oxide trenching dishing for without/or with lactitol as chemicaladditive over polishing times were tested.

The effects of lactitol containing polishing composition at different pHconditions on the oxide trenching dishing vs over polishing times wereobserved.

The test results were listed in Table 26.

As the results shown in Table 26, the polishing compositions with theaddition of lactitol, at different pH conditions afforded low oxidetrench dishing on 100 μm pitch, and 200 μm pitch respectively when 60second or 120 second over polishing times were applied.

The compositions with lactitol as oxide trench dishing reducing agentprovided significant oxide trench dishing reductions comparing to thereference polishing composition which did not have the chemicaladditive, lactitol.

TABLE 26 Effects of Lactitol at Different pH Conditions on Oxide TrenchDishing vs OP Times (Sec.) OP Times 100 um pitch 200 um pitchCompositions (Sec.) dishing dishing 0.2% Ceria-coated 0 165 291 SilicapH 5.35 Ref. 60 857 1096 120 1207 1531 0.2% Ceria-coated Silica + 0 349563 0.28% Lactitol pH 5.35 60 438 702 120 510 779 0.2% Ceria-coatedSilica + 0 73 182 0.28% Lactitol pH 7.0 60 222 390 120 346 532 0.2%Ceria-coated Silica + 0 269 386 0.28% Lactitol pH 8.0 60 425 576 120 568766

Table 27 depicted the ratio of Trench Dishing Rate (A)/Blanket HDP RR(Å/min.) at Different pH.

TABLE 27 Ratio of Trench Dishing Rate (A)/Blanket HDP RR (A/min.) atDifferent pH P100 Dishing P200 Dishing Rate (Å/min.)/ Rate (Å/min.)/Blanket HDP Blanket HDP Compositions RR (A/min.) RR (A/min.) 0.2%Ceria-coated Silica pH 5.35 0.13 0.16 0.2% Ceria-coated Silica + 0.28%0.03 0.03 Lactitol pH 5.35 0.2% Ceria-coated Silica + 0.28% 0.05 0.06Lactitol pH 7.0 0.2% Ceria-coated Silica + 0.28% 0.06 0.08 Lactitol pH8.0

As the results shown in Table 27, the addition of lactitol as oxidetrench dishing reducer in polishing composition significantly reducedthe ratio of trench dishing rate vs the blanket HDP film removal ratesat different pH conditions than that ratio obtained for reference sampleat pH 5.35.

The slopes of oxide trench dishing vs the OP removal amount at differentpH conditions was showed in Table 28.

TABLE 28 Effects of Lactitol at Different pH on Slopes of Dishing vs OPRemoval Amount P100 P200 dishing/OP dishing/OP Compositions Amt SlopeAmt Slope 0.2% Ceria-coated Silica pH 0.19 0.23 5.35 0.2% Ceria-coatedSilica + 0.04 0.06 0.28% Lactitol pH 5.35 0.2% Ceria-coated Silica +0.06 0.08 0.28% Lactitol pH 7.0 0.2% Ceria-coated Silica + 0.06 0.080.28% Lactitol pH 8.0

The results listed in Table 28 indicated that the compositions withchemical additive lactitol at different pH conditions provided lowerslopes of trench dishing vs the over polishing removal amounts whichindicated good over polishing window for maintaining low oxide trenchdishing even more oxide film removed in over polishing steps.

As showing in Table 28, lactitol and ceria-coated silica based CMPpolishing compositions again showed much lower slope values at differentpH conditions comparing to those slope values obtained for theceria-coated silica abrasive based reference sample at pH 5.35.

In Example 11, the trench oxide loss rates were compared for thepolishing compositions using lactitol at different pH conditions orwithout using lactitol at pH 5.35 and listed in Table 29.

TABLE 29 Effects of Lactitol at Different pH Conditions on Trench LossRates (Å/min.) P100Trench P200Trench Loss Rate Loss Rate Compositions(Å/sec.) (Å/sec.) 0.2% Ceria-coated Silica pH 5.35 18.5 19.3 Ref. 0.2%Ceria-coated Silica + 2.3 2.6 0.28% Lactitol pH 5.35 0.2% Ceria-coatedSilica + 3.3 4.0 0.28% Lactitol pH 7.0 0.2% Ceria-coated Silica + 3.74.2 0.28% Lactitol pH 8.0

As the results shown in Table 29, the addition of lactitol as oxidetrench dishing reducing agent into the polishing compositions atdifferent pH conditions, the trench loss rates were significantlyreduced vs the reference sample without using lactitol as chemicaladditive.

The polishing test results obtained at different pH conditions usinglactitol as oxide trench dishing reducer proved that the CMP polishingcompositions can be used in wide pH range including acidic, neutral oralkaline pH conditions.

Example 12

When using the suitable chemical additives, such as maltitol or lactitolor their derivatives, as oxide trench reducing agents in polishingcompositions, these chemical additives can have some impacts on thestability of ceria-coated inorganic oxide abrasives in the CMP polishingcompositions.

In CMP polishing compositions, it is very important to have goodabrasive particle stability to assure constant and desirable CMPpolishing performances.

Typically, the abrasive particle stability is tested through monitoringthe MPS (nm) (=mean particle size) and D99 (nm) changes vs the times orat elevated temperatures. The smaller of MPS (nm) and D99 (nm) changes,the more stable of the invented polishing compositions are.

In this example, the stability of ceria-coated silica abrasive particlesin the compositions having chemical additives was monitored by measuringthe change of the mean particles size and the change of particle sizedistribution D99.

The testing samples were made using 0.2 wt. % or other wt. %ceria-coated silica abrasive; very low concentration of biocide; 0.15wt. % maltitol, 0.15 wt. % lactitol or 0.0787 wt. % Myo-inositol asoxide trench dishing reducer; and with pH adjusted to 5.35.

The abrasive stability tests on the polishing compositions were carriedout at 50° C. for at least 10 days or more.

The MPS (nm) or D99 (nm) of the tested polishing compositions weremeasured using DLS technology (DLS=dynamic light scattering).

The stability test results of the used ceria-coated silica abrasiveswith the chemical additives were listed in Table 30.

TABLE 30 Particle Size Stability (MPS) Test Results @ 50° C. - D99 (nm)Days Compositions 0 1 2 3 4 11 18 32 0.2% Ceria-coated Silica + 0.15%Maltitol 179.6 179.6 178.4 179.6 180 183 0.2% Ceria-coated Silic + 0.15%Lactitol 180 178.8 180.9 179.6 180.6 182.3 0.2% Ceria-coated Silic +0.0787% 180.8 178.5 179.6 180.4 181.5 182.3 Myo-Inositol

By day 4 at 50° C., 0.2 wt. % ceria-coated silica particles had MPSchanges of

0.23%, 0.34% and 0.39% in the compositions having 0.15 wt. % maltitol,0.15 wt. lactitol and 0.0787 wt. % myo-inositol respectively.

0.2 wt. % ceria-coated silica particles in the composition having 0.15wt. % maltitol had a mean particle size change of less than 1.9% by day18 at 50° C.

0.2 wt. % ceria-coated silica particles in the composition having 0.0787wt. % myo-inositol had a mean particle size change of less than 0.83% byday 11 at 50° C.

0.2 wt. % ceria-coated silica particles in the composition having 0.15wt. % lactitol had a mean particle size change of less than 1.3% by day32 at 50° C.

More stability test were listed in Table 31.

TABLE 31 Particle Size Stability Test Results @ 50° C. - MPS (nm) & D99(nm) Particle Sizes Compositions (nm) Day 0 Day 1 Day 4 Day 8 Day 15 Day22 Day 33 Day 40 Day 62 0.2% Ceria-coated Silica + MPS (nm) 120 121.1122.8 123 123.2 121.5 121.9 120.6 119.9 0.15% Maltitol pH 5.35 D99 (nm)176.3 178 180.9 180.4 180 172.4 178.3 176.2 177.4

0.2 wt. % ceria-coated silica particles in the composition having 0.15wt. % maltitol had a mean particle size and D99 changes of less than8.34×10⁻⁴ and 0.63 respectively by day 62 at 50° C.

Furthermore, the particle stability tests were also conducted at 50° C.on polishing compositions comprised more concentrated ceria-coatedsilica abrasives (more than 0.2 wt. %) and more concentrated maltitol(more than 0.15 wt. %) as oxide trench dishing reducer.

The test results were listed in Table 32.

TABLE 32 Particle Size Stability Test Results 50° C. - MPS (nm) & D99(nm) Particle Sizes Compositions (nm) Day 0 Day 3 Day 5 Day 7 Day 14 Day19 Day 25 Day 42 0.8% Ceria-coated Silica + MPS (nm) 122 122 121.9 122121 121 121.4 122.5 0.6% Maltitol pH 5.35 D99 (nm) 180.5 179.5 180 179.6185.3 185.3 179.6 180.9 1.6% Ceria-coated Silica + MPS (nm) 121.2 122.1122.1 121.5 121.3 121.2 121.4 122.6 1.2% Maltitol pH 5.35 D99 (nm) 179.5180 180 179.2 179.6 179.6 180.5 182.3 2.4% Ceria-coated Silica + MPS(nm) 122.1 121.9 121.5 121.1 121 121 122 122.5 1.8% Maltitol pH 5.35 D99(nm) 180.5 180 179.2 178 180.1 180.1 180.5 180.9

Data showed that 0.8 wt. % of the ceria-coated silica particles had MPSand D99 changes of less than 0.41% and less than 0.23% respectively byday 42 at 50° C. in the composition having 0.6 wt. % of maltitolrespectively.

Data also showed that 0.8 wt. % of the ceria-coated silica particles hadMPS and D99 changes of less than 0.41% and less than 0.23% respectivelyby day 42 at 50° C. in the composition having 0.6 wt. % of maltitolrespectively.

1.6 wt. % of the ceria-coated silica particles had MPS and D99 changesof less than 1.2% and less than 1.6% respectively by day 42 at 50° C. inthe composition having 1.2 wt. % of maltitol respectively.

2.4 wt. % of the ceria-coated silica particles had MPS and D99 changesof less than 0.33% and less than 0.23% respectively by day 42 at 50° C.in the composition having 1.8 wt. % of maltitol respectively.

As the results shown in Table 30 to 32, when maltitol, lactitol orMyo-inositol used as oxide trench dishing reducer with ceria-coatedsilica particles as abrasives, the polishing compositions showed verygood particle size stability of MPS (nm) and D99 (nm) even at elevatedtesting temperatures.

The polishing compositions comprised of ceria-coated colloidal silicaabrasives and more concentrated maltitol as oxide trench dishing reducerall showed very good particle size stability of MPS (nm) and D99 (nm) atelevated temperatures.

Example 13

Another key benefit of using the present invented CMP polishingcompositions is the reduced total defect counts through andpost-polishing which is resulted in by using the ceria-coated colloidalsilica composite particles as abrasives instead of using calcined ceriaparticle as abrasives.

The following three polishing compositions were prepared for defectstesting. The first sample was made using 0.5 wt. % calcined ceriaabrasives, 0.05 wt. % polyacrylate salt and low concentration ofbiocide; the second sample was made using 0.2 wt. % ceria-coated silicaabrasives, 0.28 wt. % maltitol and low concentration of biocide; thethird sample was made using 0.2 wt. % ceria-coated silica abrasives,0.28 wt. % lactitol and low concentration of biocide. In order to obtainsimilar dielectric film removal rates to be compared, higherconcentration of calcinated ceria abrasive was used in sample 1.

All three formulations have pH valued at 5.35.

The total defect counts on polished TEOS and SiN wafers were compared byusing three afore listed polishing compositions. The total defect countresults were listed in Table 33.

TABLE 33 Effects of Different Polishing Compositions on TEOS & SiN TotalDefect Counts TEOS Total Defect SiN Total Defect Count@0.13 μmCount@0.13 μm Compostions LPD LPD 0.2% Calcined Ceria + 0.05% 3847 498Polyacrylate Salt pH 5.35 0.2% Ceria-coated Silica + 0.28% 438 73Maltitol pH 5.35 0.2% Ceria-coated Silica + 0.28% 493 73 Lactitol pH5.35

As the total defect count results shown in Table 33, the polishingcompositions using ceria-coated silica particles as abrasives and eitherof maltitol or lactitol as trench dishing reducing agent affordedsignificantly lower total defect counts on the polished TEOS and SiNwafers than the total defect counts obtained using the polishingcomposition comprised of calcined ceria abrasives and polyacrylate saltas chemical additive.

Example 14

The following four polishing compositions were prepared for the defectstesting.

The first two polishing compositions used calcined ceria abrasives, 0.28wt. % maltitol or 0.28 wt. % lactitol as oxide trenching dishingreducing agent and low concentration of biocide; the other two polishingcompositions were made using ceria-coated silica abrasives, 0.28 wt. %maltitol or 0.28 wt. % lactitol as oxide trenching dishing reducingagent and low concentration of biocide. All four formulations have pHvalued at 5.35.

All chemical additives used at the same wt. %, but different types ofabrasives were used, e.g., calcined ceria vs ceria-coated silicaparticles as abrasives.

The effects of different types of abrasives on the film removal ratesand TEOS: SiN selectivity were observed and the results were listed intable 34.

TABLE 34 Effects of Different Types of Abrasives on Film RR & TEOS: SiNSelectivity TEOS RR HDP RR SiN RR TEOS: SiN Compositions (A/min.)(A/min.) (A/min.) Selectivity Calcined Ceria + 1774 1839 38 43 0.28%Maltitol Calcined Ceria + 1997 1996 37 54 0.28% Lactitol Ceria-coatedSilica + 3085 2956 60 51 0.28% Maltitol Ceria-coated Silica + 3188 288569 46 0.28% Lactitol

As the results shown in Table 34, the polishing compositions that usedceria-coated silica as abrasives did afford much higher TEOS and HDPfilm removal rates than those film removal rates obtained from thepolishing compositions which used calcined ceria as abrasives.

The normalized total defect counts on polished TEOS and SiN wafers werecompared by using four afore listed polishing compositions. Thenormalized total defect count results were listed in Table 35.

TABLE 35 Effects of Different Types of Abrasives on Normalized TEOS &SiN Total Defect Counts TEOS TEOS 0.07 um 0.13 um PECVD SiN PECVD SiNCompositions LPD LPD 0.1 um LPD 0.13 um LPD Calcined Ceria + 1.00 1.001.00 1.00 0.28% Maltitol Calcined Ceria + 1.03 0.64 0.96 1.04 0.28%Lactitol Ceria-coated Silica + 0.21 0.07 0.25 0.58 0.28% MaltitolCeria-coated Silica + 0.43 0.10 0.49 0.58 0.28% Lactitol

As the normalized total defect count results shown in Table 35, thepolishing compositions using ceria-coated silica particles as abrasivesand either maltitol or lactitol as trench dishing reducing agentafforded significantly lower normalized total defect counts on thepolished TEOS and SiN wafers than the normalized total defect countsobtained using the polishing composition comprised of calcined ceriaabrasives, and either maltitol or lactitol as oxide trench dishingreducing chemical additive.

Example 15

In Example 15, both calcined ceria and ceria-coated silica particlesbased polishing compositions were tested.

The composition comprising calcined ceria particles but no chemicaladditives was used as a reference.

Calcined ceria or ceria-coated silica particles were used at 1.0 wt. %,D-sorbitol and D-Mannitol were used at 2.0 wt. % respectively.

All samples have alkaline pH at 9.5. IC1010 used as polishing pad, and3.3 psi down force was applied.

The film removal rate results were listed in Table 36.

TABLE 36 Film Removal Rates (A/min.) vs Polishing Compositions TEOS RRHDP RR SiN RR Compositions (Å/min.) (Å/min.) (Å/min.) 1.0% CalcinedCeria pH 9.5 Ref. 3509 3290 227 1.0% Calcined Ceria + 2.0% 118 121 28D-sorbitol pH 9.5 1.0% Calcined Ceria + 2.0% 181 144 29 D-mannitol pH9.5 1.0% Ceria-coated Silica + 2.0% D- 133 137 39 sorbitol pH 9.5

As the results shown in Table 36, when no chemical additive was used inpolishing composition, the polishing composition with 1.0 wt. % calcinedceria abrasives afforded high TEOS and HDP film removal rates at pH 9.5.

With either D-sorbitol or D-mannitol used at 2.0 wt. % as chemicaladditive in the polishing compositions at pH 9.5, much lower TEOS andHDP film removal rates were obtained.

It appears that the polishing compositions with such low TEOS and HDPfilm removal rates cannot meet the oxide film removal rate requirementsin CMP applications.

It is very important to identify the suitable concentration range andthe suitable ratios of abrasive/chemical additive, and optimized pHconditions in the CMP polishing compositions which are able to providehigh enough oxide film removal rates and high TEOS: SiN selectivity tosatisfy the CMP application needs.

Example 16

In Example 16, the weight % ratios of ceria-coated silica vs thechemical additive D-sorbitol were tested on their effects on variousfilm polishing removal rates and on oxide trench dishing vs overpolishing times.

In the composition, the ceria-coated silica abrasives was used from 0.2wt. % to 0.4 wt. %, and D-sorbitol was used from 0.0 wt. % to 0.30 wt.%; which gave the ratio of ceria-coated silica abrasive wt. % vs thechemical additive D-sorbitol wt. % from 0.0 to 4.0. pH was 5.35 for alltesting compositions.

The test results were depicted in FIGS. 1 and 2 respectively.

Please note, three points at 0 for both figures were for the compositionhaving abrasive particles only i.e., not for the ratio of ceria-coatedsilica vs D-sorbitol, since no D-sorbitol was used in the composition.

As the results shown in FIGS. 1 and 2, when the weight % ratios ofceria-coated silica vs D-sorbitol ranged from 0.0 to 4.0, high TEOS andHDP film removal rates were high.

But at ratio of 0.0, SiN removal rate was also high, therefore, theselectivity of TEOS: SiN is low.

When the ratio of ceria-coated silica vs D-sorbitol was ranged from 0.7to 2.0, the high TEOS and HDP film removal rates, low SiN removal rates,and high TEOS: SiN selectivity were achieved.

When this ratio was >2.0, the SiN removal rate was increased graduallyand the selectivity of TEOS: SiN was decreased.

The oxide trench dishing vs over polishing times shown in FIG. 2 alsoshown that between 0.7 to 2.0 weight % ratio range for ceria-coatedsilica vs D-sorbitol was more suitable range for achieving high oxidefilm removal rates, low SiN removal rates, high TEOS: SiN selectivityand low oxide trench dishing.

The test results shown that the selection of the suitable ratio range ofceria-coated silica abrasive wt. % vs the chemical additive D-sorbitolwt. % allows the high oxide film removal rates, low SiN film removalrates, high selectivity of Oxide: SiN films, and low oxide trenchdishing.

Example 17

In this Example, calcined ceria as abrasives and polyacrylate salt (PAASalt) and sorbitol with different concentrations were used as chemicaladditives to compare the polishing performances at pH 5.35. 3.0 psi downforce was applied in these polishing tests. The composition withoutusing chemical additive was used as a reference.

The testing results were listed in Table 37.

TABLE 37 Effects of Additive Conc. on Film RR (A/min.) & Selectivity ofOxide: SiN TEOS-RR HDP-RR PECVD SiN TEOS: SiN Samples (ang/min)(ang/min) (ang/min) Selectivity Calcined Ceira only 2210 2313 110 20Ceria + 0.05X PAA 1657 1627 97 17 Salt Ceria + 0.05X 1956 1990 68 29D-Sorbitol Ceria + 0.15X 1602 1579 49 33 D-Sorbitol Ceria + 0.3X 12941179 43 30 D-Sorbitol

As the results showed in Table 37, the chemical additive, PAA salt incalcined ceria particle-based formulation suppressed TEOS and HDP filmremoval rates and reduced SiN film removal rate and TEOS: SiNselectivity.

The chemical additive, D-sorbitol, when used in three differentconcentrations in calcined ceria particles based CMP polishingcompositions also suppressed TEOS and HDP film removal rates, butsignificantly reduced SiN removal rates and thus increased TEOS: SiNselectivity from 20:1 to around 30:1.

The effects of chemical additives, PAA Salt and 3 differentconcentrations of D-sorbitol plus same concentrations of calcined ceriaabrasive based polishing compositions on the various sized oxide trenchdishing vs over polishing times were observed. The results were listedin Table 38.

As the results showed in Table 38, the chemical additive, PAA salt incalcined ceria particle-based formulation reduced oxide trench dishingwhile comparing to the calcined ceria only based reference.

TABLE 38 Effects of Additives or Conc. on Oxide Trench Dishing (A) 100um 200 um 1000 um Over Polish pitch pitch pitch Samples Time (Sec.)dishing (A) dishing (A) dishing (A) Calcined Ceria 0 96 184 779 only 60949 1238 2043 Ceria + 0.05X 0 91 210 954 PAA Salt 60 117 228 990 Ceria +0.05X 0 100 219 783 D-Sorbitol 60 226 366 1126 Ceria + 0.15X 0 101 213700 D-Sorbitol 60 166 280 787 Ceria + 0.3X 0 93 206 811 D-Sorbitol 60109 236 834

The chemical additive, D-sorbitol, when used in three differentconcentrations in calcined ceria particles based CMP polishingcompositions also reduced oxide trench dishing across three differentsized features.

When D-sorbitol used at 0.15× or 0.3× concentrations, much lower oxidetrench dishing obtained than that from D-sorbitol used at 0.05×concentration vs 60 second over polishing time.

Example 18

In Example 18, the CMP polishing compositions were tested at differentpH values.

The compositions composing of 0.5 wt. % calcined ceria as abrasives onlyor with 0.15 wt. % D-sorbitol as chemical additive.

Film removal rates were tested at two different pH conditions.

Tests on film removal rates, TEOS: SiN selectivity and oxide trenchdishing were performed.

The results were listed in Table 39 and Table 40 respectively.

TABLE 39 Effects of pH on Film Removal Rates & TEOS: SiN SelectivityTEOS-RR HDP-RR PECVD SiN TEOS: SiN Samples (ang/min) (ang/min) (ang/min)Selectivity Calcined Ceira 2210 2313 110 20 only, pH 5.35 Ceria + 0.15X1602 1579 49 33 D-Sorbitol pH 5.35 Ceria + 0.15X 1467 1697 40 37D-Sorbitol pH 9.39

As the results showed in Table 39, when the STI polishing compositionhaving 0.5 wt. % calcined ceria particles as abrasives and 0.15 wt. %D-sorbitol as a chemical additive, slightly lower TEOS removal rate wasobtained at acidic pH and slightly higher HDP film removal rate wasobtained at alkaline pH, and SiN removal rate was reduced from 49 Å/min.at pH 5.35 to 40 Å/min. at pH 9.39.

TABLE 40 Effects of pH Conditions on Oxide Trench Dishing (A) 1000 μm OPPitch Times 100 μm Pitch 200 μm Pitch Dsihing Samples (sec.) Dsihing (Å)Dsihing (Å) (Å) Calcined Ceria only 0 96 184 779 pH 5.35 60 949 12382043 Calcined Ceria + 0.5% 0 101 213 700 D-sorbitol pH 5.35 60 166 280787 Calcined Ceria + 0.5% 0 104 220 982 D-sorbitol pH 9.39 60 176 3211140

As the results showed in Table 40, when the polishing composition having0.5 wt. % calcined ceria particles as abrasives and 0.15 wt. %D-sorbitol as a chemical additive, low oxide trench dishing obtained on100 μm and 200 μm pitch respectively at both pH values. Even at pH 9.39,0.5 wt. % calcined ceria particles as abrasives and 0.15 wt. %D-sorbitol used as a chemical additive still affords more stable oxidetrench dishing vs over polishing time increases.

Thus, the CMP polishing compositions provide good dishing performance ata wide pH range for CMP applications.

Example 19

In Example 19, polishing testes were on various films using the CMPpolishing compositions made with calcined ceria particles orceria-coated silica particles as abrasives and maltitol or lactitol aschemical additives at pH 5.35.

The polishing pad used was Dow's IC1010 pad, the down force used forpolishing tests was 3.0 psi.

The test results on various film removal rates and TEOS: SiN selectivitywere listed in Table 41.

TABLE 41 Film RR (A/min.) & TEOS: SiN Selectivity Comparison TEOS RR HDPRR SiN RR TEOS: SiN Compositions (A/min.) (A/min.) (A/min.) SelectivityCalcined Ceria pH 5.35 Ref. 1 2210 2313 110 20 Calcined Ceria + 0.15%Maltiol 2257 2235 40 56 Ceria-coated Silica + 0.28% Maltitol 1774 183938 43 Ceria-coated Silica + 0.28% Lactitol 1997 1996 37 54 Ceria-coatedSilica pH 5.35 Ref. 2 3279 2718 349 9 Ceria-coated Silica + 0.15%Maltitol 3157 2747 43 73 Ceria-coated Silica + 0.28% Maltitol 3085 295660 51 Ceria-coated Silica + 0.28% Lactitol 3188 2885 69 46

As the results shown in Table 41, the polishing compositions havingchemical additive maltitol or lactitol with either calcined ceriaparticles or ceria-coated silica particles offered high TEOS and goodHDP film removal rates, significantly suppressed SiN film removal rates,thus, increased TEOS: SiN selectivity significantly.

Oxide trench dishing vs over polishing times at pH 5.35 were tested.

TABLE 42 Effects of Chemical Additives on Trench Dishing vs OP Times(sec.) 200 μm 100 μm Pitch Pitch OP Times Dishing Dishing Compositions(sec.) (Å) (Å) Calcined Ceria pH 5.35 Ref. 1 0 96 184 60 949 1238 120Calcined Ceria + 0.15% Maltiol 0 200 392 60 268 463 120 337 565Ceria-coated Silica + 0.28% Maltitol 0 144 318 60 168 373 120 234 407Ceria-coated Silica + 0.28% Lactitol 0 155 319 60 198 352 120 245 439Ceria-coated Silica pH 5.35 Ref. 2 0 165 291 60 857 1096 120 1207 1531Ceria-coated Silica + 0.15% Maltitol 0 198 347 60 392 562 120 503 707Ceria-coated Silica + 0.28% Maltitol 0 174 343 60 273 455 120 371 566Ceria-coated Silica + 0.28% Lactitol 0 189 361 60 309 501 120 406 651

The polishing pad used was Dow's IC1010 pad, the down force used forpolishing tests was 3.0 psi.

The test results on oxide trench dishing vs over polishing times werelisted in Table 42.

As the results shown in Table 42, whether using calcined ceria orceria-coated silica particles as abrasives, the polishing compositionshaving maltitol or lactitol at lower or higher concentrations veryeffectively reduced the oxide trench dishing vs over polishing timesacross various sized oxide trench features, and also provide moreuniform and stable over polishing windows.

Example 20

All tested CMP polishing compositions had pH values at 5.35. Dow'sIK4140 pad was used to replace Dow's IC1010 for

When Dow's IK4140 pad was used, 4.3 psi DF was applied for polishingwith calcined ceria abrasive based polishing composition, and 2.5 psi DFwas applied with ceria-coated silica abrasive based polishingcompositions. The same table/head speeds at 50/48 rpm were applied forall polishing compositions.

The test results on polishing various types of blanket wafers usingDow's IK4140H polishing pad were listed in Table 43.

TABLE 43 Various Polishing Compositions@Different Polishing DF vs FilmRR(A/min.) & Selectivity HDP Film SiN Film RR HDP: SiN Compositions RR(Å/min.) (Å/min.) Selectivity 0.5% Ceria + 0.0506% 1428 100 14.3Polyacrylate salt pH 5.35 @4.3 psi DF 0.2% Ceria-coated Silica + 1455 6123.9 0.15% D-Sorbitol pH 5.35 @2.5 psi DF 0.2% Ceria-coated Silica +1490 72 20.1 0.15% Maltitol pH 5.35 @2.5 psi DF 0.2% Ceria-coatedSilica + 1502 53 28.3 0.28% Maltitol pH 5.35 @2.5 psi DF

As the results shown in Table 43, when different polishing down forcesused for different polishing compositions to polish various blanketfilms, very similar HDP film removal rates were obtained.

The polishing compositions using ceria-coated silica abrasives gavesimilar HDP film removal rates even at much lower applied down force andwith lower abrasive concentrations comparing with the HDP film removalrate obtained at 4.3 psi DF using calcined ceria abrasive basedpolishing composition.

Also, in overall, ceria-coated silica abrasive containing polishingcompositions gave lower SiN removal rates than the polishing compositionusing ceria particles as abrasives while comparing their SiN removalrates obtained at different polishing down forces.

The polishing test results on polishing patterned wafers at differentdown forces were listed in Table 44.

TABLE 44 Various Polishing Compositions@Different Polishing DF onPolishing Patterned Wafers P200 Trench P200 SiN P200 SiN/HDP Loss RateLoss Rate Blanket Compositions (Å/sec.) (Å/sec.) Ratio 0.5% Ceria +0.0506% 2.1 0.9 0.038 Polyacrylate salt pH 5.35 @4.3 psi DF 0.2%Ceria-coated Silica + 1.9 0.6 0.025 0.15% D-Sorbitol pH 5.35 @2.5 psi DF0.2% Ceria-coated Silica + 2.4 0.7 0.028 0.15% Maltitol pH 5.35 @2.5 psiDF

As the patterned wafer polishing results shown in Table 44, whenceria-coated silica particles were used as abrasives and D-sorbitol ormaltitol as chemical additive, the polishing compositions gave similarP200 oxide trench loss rates, lower P200 SiN loss rates and also lowerSiN/HDP blanket ratio than the polishing composition using calcinedceria particles as abrasives and polyacrylate salt as chemical additive.

In another set of tests shown in Table 45, Dow's IK4250UH pad was alsoused with 3.0 psi DF for both polishing compositions. For the polishingtests, the same table/head speeds at 87/93 rpm were applied.

The polishing test results on polishing various types of blanket wafersusing Dow's IK4250UH polishing pad were listed in Table 45.

TABLE 45 Various Polishing Compositions vs Film RR(A/min.) & SelectivityHDP Film SiN Film RR HDP: SiN Compositions RR (Å/min.) (Å/min.)Selectivity 0.5% Ceria + 0.0506% 2715 196 13.9 Polyacrylate salt pH 5.350.2% Ceria-coated Silica + 5913 114 51.9 0.15% D-Sorbitol pH 5.35

As the results shown in Table 45, at same pH conditions, when using 0.2wt. % ceria-coated silica particles as abrasives, and 0.15 wt. %D-Sorbitol as additives, the more suppressed SiN removal rate wasobtained and 118% higher HDP film removal rate was achieved whilecomparing with the results using the polishing composition comprised of0.5 wt. % calcined ceria particles as abrasives and 0.0506 wt. %polyacrylate salt as additive while using Dow's IK4250UH polishing pad.

At the same time. the HDP film: SiN selectivity was increased from13.9:1 to 51.9:1.

The patterned wafers were also polished using Dow's IK4250UH pad. Thepolishing results and polishing compositions were listed in Table 46.

TABLE 46 Various Polishing Compositions on Polishing Patterned WafersP200 Trench P200 SiN P200 SiN/HDP Loss Rate Loss Rate BlanketCompositions (Å/sec.) (Å/sec.) Ratio 0.5% Ceria + 0.0506% 6.1 2.2 0.048Polyacrylate salt pH 5.35 0.2% Ceria-coated Silica + 4.3 1.3 0.013 0.15%D-Sorbitol pH 5.35

As the results shown in Table 46, lower P200 oxide trench loss rates,lower P200 SiN loss rates and also lower SiN/HDP blanket ratio wereobtained when ceria-coated silica particles were used as abrasives andD-sorbitol as chemical additive.

The embodiments of this invention listed above, including the workingexample, are exemplary of numerous embodiments that may be made of thisinvention. It is contemplated that numerous other configurations of theprocess may be used, and the materials used in the process may beelected from numerous materials other than those specifically disclosed.

The invention claimed is:
 1. A Chemical Mechanical Polishing(CMP)composition comprising: abrasive particles selected from the groupconsisting of inorganic oxide particles, metal-coated inorganic oxideparticles, organic polymer particles, metal oxide-coated organic polymerparticles, and combinations thereof; chemical additive; solvent selectedfrom the group consisting of deionized (DI) water, distilled water, andalcoholic organic solvents; and optionally biocide; and pH adjuster;wherein the composition has a pH of 3 to 10; the abrasive particles havea mean particle size of 120 to 500 nm and have a concentration from 0.05wt. % to 10 wt. %; the inorganic oxide particles are selected from thegroup consisting of ceria, colloidal silica, high purity colloidalsilica, colloidal ceria, alumina, titania, zirconia particles, andcombinations thereof; the metal-coated inorganic oxide particles areselected from the group consisting of ceria-coated inorganic oxideparticles selected from the group consisting of ceria-coated colloidalsilica, ceria-coated high purity colloidal silica, ceria-coated alumina,ceria-coated titania, ceria-coated zirconia particles and combinationsthereof; the organic polymer particles are selected from the groupconsisting of polystyrene particles, polyurethane particles,polyacrylate particle, and combinations thereof; the metal-coatedorganic polymer particles are selected from the group consisting ofceria-coated organic polymer particles, zirconia-coated organic polymerparticles, silica-coated organic polymer particles, and combinationsthereof; the abrasive particles have changes of mean particle size MPS(nm) and D99 (nm)≤3.0% over shelf time of ≥30 days at a temperatureranging from 20 to 60° C.; wherein D99 (nm) is a particle size that 99wt. % of the particles fall on and under; and the chemical additiveranges from 0.05 wt. % to 5 wt. %; and has a molecular structure (a):

wherein the structure (a) has at least six hydroxyl functional groups inits molecular structure; and R1, R2, R3, R4 and R5 (Rs in group of R1 toR5) are selected as following (i) at least one R in the group of R1 toR5 is a polyol molecular unit having a structure shown in (b):

wherein m or n is independently selected from 1 to 5; and each of R6,R7, R8 and R9 is independently selected from the group consisting ofhydrogen, alkyl, alkoxy, organic group with one or more hydroxyl groups,substituted organic sulfonic acid or salt, substituted organiccarboxylic acid or salt, organic carboxylic ester, organic amine, andcombinations thereof; (ii) at least one R in the group of R1 to R5 is asix-member ring polyol as shown in (c):

wherein one of OR in group of OR11, OR12, OR13 and OR14 will be replacedby O in structure (a); and R10 and each of other R in group of R10, R11,R12, R13 and R14 is independently selected from the group consisting ofhydrogen, alkyl, alkoxy, organic group with one or more hydroxyl groups,substituted organic sulfonic acid or salt, substituted organiccarboxylic acid or salt, organic carboxylic ester, organic amine, andcombinations thereof; and (iii) each of other Rs in the group of R1 toR5 is independently selected from the group consisting of hydrogen,alkyl, alkoxy, organic group with one or more hydroxyl groups,substituted organic sulfonic acid or salt, substituted organiccarboxylic acid or salt, organic carboxylic ester, organic amine, andcombinations thereof.
 2. The Chemical Mechanical Polishing(CMP)composition of claim 1, wherein the polyol molecular unit (b) which hasn=2 and m=1; and rest of Rs in the group of R1 to R14 are all hydrogenatoms, as shown below:

and the solvent is deionized (DI) water, and the abrasive particles havechanges of mean particle size MPS (nm) and D99 (nm)≤2.0%.
 3. TheChemical Mechanical Polishing(CMP) composition of claim 1, wherein theabrasive particles are ceria-coated colloidal silica particles or ceriaparticles.
 4. The chemical mechanical polishing composition of claim 1,wherein the composition comprises ceria-coated colloidal silicaparticles or ceria particles; and the ceria-coated colloidal silicaparticles or ceria particles have changes of mean particle size MPS (nm)and D99 (nm)≤2.0% over shelf time of ≥30 days at a temperature rangingfrom 20 to 60° C.; wherein D99 (nm) is a particle size that 99 wt. % ofthe particles fall on and under.
 5. The chemical mechanical polishingcomposition of claim 1, wherein the composition comprises one selectedfrom the group consisting of from 0.0001 wt. % to 0.05 wt. % of thebiocide having active ingredient selected from the group consisting of5-chloro-2-methyl-4-isothiazolin-3-one, 2-methyl-4-isothiazolin-3-one,and combinations thereof; from 0 wt. % to 1 wt. % of the pH adjustingagent selected from the group consisting of nitric acid, hydrochloricacid, sulfuric acid, phosphoric acid, other inorganic or organic acids,and mixtures thereof for acidic pH conditions; or selected from thegroup consisting of sodium hydride, potassium hydroxide, ammoniumhydroxide, tetraalkyl ammonium hydroxide, organic quaternary ammoniumhydroxide compounds, organic amines, and combinations thereof foralkaline pH conditions; and combinations thereof.